Bedwetting is embarrassing for children, and its reasons are frequently misunderstood by parents, said Dr. John Kryger, a pediataric urologist with American Family Children's Hospital in Madison. Bedwetting can be simply out of the child's control.

"A large part of the problem is a delay in the maturity of the central nervous system and interaction between the child's brain, sleep patterns and bladder-control center," he says. "Practically every bedwetter I see is a deep sleeper, and when children go into a deep sleep, brain patterns change and affect bladder control."

"At night, the brain secretes a hormone that helps the kidneys retain water so you don't produce as much urine," adds Kryger. "Children who are bedwetters seem to make more urine than average children, and their bladders overflow quicker because of that."

Kryger says 15 percent of kids still wet the bed at age five, but the rate declines 15 percent every year until the age of 18. Bedwetting is often inherited from other family members. Early in childhood, more boys than girls are likely to wet the bed, but after age seven, the number is about equal for both sexes.

"When a patient comes to me, and they are five years old, I tell them they will get better in time," he says. "I just don't know if it will be in a year, five years, or ten years. There is no way to predict when they will achieve dryness."

According to Kryger, kids can reduce the chances of wetting the bed by not drinking fluids one hour before bedtime, reducing caffeine intake, and cutting back on food consumption so the bowel doesn't press against the bladder and lower its capacity for urine. If these fail, other methods may be used, including an alarm attached to the child's underwear.

"When it gets wet, the alarm vibrates or rings so the child is startled from sleep," he said. "Over time, the fullness of the bladder awakens the child before the alarm goes off. It's a principle that involves conditioning the body to awaken (when the bladder is full)."

Kryger says alarms cure 60 percent of bedwetters, but they can be a nuisance.

"The alarm sometimes startles the whole household, everybody wakes up, but the deep sleeper who is wetting the bed just sleeps through it," he says. "I tend to favor medications because all you have to do is take a tablet before bedtime."

Kryger says one commonly used drug is desmopressin, a hormone that signals the kidneys to retain water, so less urine is produced while the child is asleep. Desmopressin also has a 60 percent success rate in curing bedwetters.

"There are virtually no side effects and for the fortunate ones, it may work overnight," he says. "Some may use it for special occasions like sleepovers, camping trips, and not worry about the bedwetting other days of the week."

If desmopressin is not successful, it can be combined with a second drug called imipramine, which allows greater urine retention by relaxing the bladder and reducing deep sleep patterns. However, Kryger says some doctors fear combining the two drugs because of possible side effects.

"There could be behavior changes in which children get angry or emotional, and that can be disruptive to the family," he says. "It may also cause insomnia and in high doses, it has been linked to changes in heart rhythm and seizures."

Yet, Kryger says his experience with the drug combination has shown limited side effects and has been more successful at curing bedwetting than using either drug alone.

Aside from drugs and other therapies, Kryger makes it clear to parents that their child has no control over bedwetting, and punishment or negative reactions will not solve the problem. He promotes positive motivation that may lead to dry nights.

"A lot of kids view bedwetting as the parents' problem, because the parents are most bothered by it," he says. "Yet, the child may be helped more if they receive an award after achieving dryness for a certain number of nights. We want them to be motivated to take their medication, avoid drinking fluids in excessive amounts before bedtime, and eat a healthier diet that helps their bowel habits."

Kryger says as children get older, they should take responsibility for changing the bed linens and doing the laundry when they have wetting accidents. He says these things are not meant to punish, but hold kids liable for their health issues.

"There is no magic bullet that cures it," he says. "A multitude of factors cause it and a multitude of therapies need to be incorporated simultaneously to cure it. If you combine these things into a program, I think we can achieve much greater success in the management of bedwetting."